The present invention relates to a modular selection button for actuating contact elements, the modular selection button including a rotating handle and at least one switch plunger supported in a housing.
German Patent Publication DE-C2-35 41 390 describes such a selection button featuring a rotating handle, a transmission member, and stops. The substantially cylindrical transmission member is non-rotatably coupled to the handle, carries an axially acting switching cam which is closed upon itself as well as a stop boss, and is supported in a housing. To limit the angle of rotation, the stops cooperate with the stop boss and are formed in stop rings of which one is replaceably and non-rotatably arranged in the housing. Located between the stops is a circular path segment which, from stop ring to stop ring, spans a different angle and with which in each case the stop boss engages. The switching cam is configured as a projecting shoulder at the lateral surface of the transmission member and cooperates with at least one switch plunger of a contact element. The switch plunger is arranged in the housing in a manner that it is non-rotatable as well as axially movable against the action of a spring and intended to actuate the contact plunger of the contact element. The direction of rotation of the handle determines which of the two switch plungers is moved. The rotation of the handle which is limited by the respective stop ring determines, on one hand, the number of possible switching positions, that is two or three switching positions and, on the other hand, the actuation mode which is the momentary contact mode, i.e., monostable, when rotated by 45° whereas it is the latching mode, i.e., bistable, when rotated by 90°. It is a disadvantage that, for changing the actuation mode, the user has to disassemble the selection button to replace the stop ring.